Magnetic drive for ships



March 6, 1956 H. A. GENTILE MAGNETIC DRIVE FOR SHIPS 2 Sheets-Sheet 1Filed May 15, 1953 March 6, 1956 Filed May 15, 1953 H. A. GENTILE2,737,145

MAGNETIC DRIVE FOR SHIPS 2 Sheets-Sheet 2 INVENTOR. HEMQY A. C-EwrmeUnited States Patent" O MAGNETICDRWEFOR SHIPS- Henry A. Gentile,Barrington, R. I.

Application May 15, 1953, serial-No. 355,307

z" claims. (el. 11s- 34)- This inventionrelates to an' improvedelectrical propulsion system for boats..

A main object of the invention is' to provide a novel and improvedelectrical propulsion system for boats, ships and the like, the' systeminvolving inexpensive' components, being reliable in operation, andproviding smooth control.

A further object' of the'invention is to provide an improved electricalpropul'sion system for a` boat, said system eliminating the necessityfor making openings in the hull of the boat for ther propeller shaft,whereby the hull is rendered completely watertight, the system beingeasy to install, being elcient noperation; and`-reducing to a minimumlosses such as those producedL by turbulence o the like.4

Further objects and advantages of the invention will become apparentfrom the following: description and claims, and from the acompanyingdrawings, wherein:

Figure 1 is a horizontal cross` sectional View taken through the hull ofa boat constructed inv accordance with the present; invention and'provided' with an improved electrical propulsion'A system accordingthereto.

Figure 2: is' a'fragnrentary si'd'e elevational view, partly in verticalcross section, of the hull of the boat shown in Figure l.

Figure 3 is an enlarged vertical cross sectional view taken on the line3 3 of Figure 2.

Figure 4 is an enlarged vertical cross sectional view taken on the line4-4 of Figure 3.

Figure 5 is a horizontal cross sectional view taken on the line 5-5 ofFigure 4.

Referring to the drawings, 1p1 generally designates a boat hull, saidhull being formed of non-magnetic material, such as plastic sheetmaterial, the hull being formed with the longitudinally extending,downwardly facing bottom channel 12 in which are located a plurality ofpropellers 13, the propellers being spaced longitudinally and also beinglaterally staggered along the channel 12.

Referring to Figure 3, it will be seen that each propeller 13 is mountedon a substantially longitudinally extending horizontal shaft 14 which isjournaled in a housing 15 having an enlarged top portion 16 which issecured to the top wall 17 of the channel 12. As shown in Figures 3, 4and 5, the annular enlarged housing portion 16 may be provided with aplurality of outwardly extending locking lugs 18 which are received insocket elements 19 integrally formed with the top wall 17 of channel 12,said socket elements 19 being arranged to receive the lugs 18 and thehousing 15 being rotatable to lock the lugs 18 in the socket elements19, a resilient deformable annular gasket 20 being interposed betweenthe annular peripheral portion 21 of the housing member 16 and thesurface of the wall 17.

Vertically journaled in the housing 15 is the worm shaft 22 providedwiththe worm 23 which meshes with the worm gear 24 secured on the associatedpropeller shaft 14. Secured to the top end of each worm shaft 22 is arotor 25 of non-magnetic material on which is se- 2,737,145 PatentedMar. 6, 1956 ICC cured the circularly arranged series of permanentmagnets 26. The permanent' magnets 26 are generally U- shaped and havetheir poles projecting upwardly, the poles being arranged in alternatingpolarity, as shown. in Figure' 5. The poles project closely adjacent tothe bottom surface of the wall 17 of channel 12, as shown in Figures'v 4and 5.

Mounted on the wall 17 are the respective electric motors 28, themotorsbeing vertically arranged and being in alignment with the wormshafts 22. The shaft 29 of each motor has secured to its lower end arotor 30 ofY nonmagnetic material in which is mounted a series ofcircularly arranged electromagnets 31, the electromagnets 31 beingarranged on a radius equal to the radius ofthe locus of the permanentmagnets 26, whereby electromagnets 3'1 are in vertical alignment withthe respective permanent magnets 26.V Preferably, the same number ofelectromagnets 31 is provided as permanentI magnets 26, and the cores ofthe electromagnets 31 are preferably of the same size and shape as thepermanent magnets 26 and are arranged inopposing relationship to thepermanent magnets, as shown in Figure 3. The pole faces of theelectromagnets 31 terminate closely adjacent to the upper surface of theto-p wall 17 of channel 12whereby the .gap between the pole faces of theelectromagnets 31 and' the pole faces of the permanent magnets 26 isminimized. Since the wall 17 of channel 12 is relatively thin and sincesaid wall is made of non-magnetic material, such as sheet plasticmaterial or the like, the wall 17 introduces relatively small reluctancein the magnetic path between the electromagnets 31r and the permanentmagnets 26, and thus substantial torque can be transmitted from therotor 30 to the rotor 25 by means of the magneticl coupling between theelectromagnets 31 and the permanent magnets 26.

Asshown in Figure 4, the rotor 3i) is provided with a peripheral' ilange32' in which are mounted the slip rings 33 and 34, said slip rings beingengaged by respective brush members 35 and 36 resiliently supported in ahousing 37 mounted on the wall 17. Connected to the contact brushes 35and 36 are the supply wires 37 and 38 which are connected by wires 39and 40 to the main supply wires 41 and 42 connected to the electricmotors 2S. As shown in Figure l, the wires 41 and 42 are connected bysuitable conductors 43 and 44 to the respective stationary terminals ofa double pole reversing switch 45 located in the control tower of theboat. One of the poles 46 of the switch 45 is connected through acontrol rheostat 47 to a generator wire 48 and the opposite switch pole49 is connected to another generator wire 50. The generator wires 48 and50 are connected through a master switch 51 to the output terminals ofthe generator 52, said generator being driven in a conventional manner,as by a turbine 53. Thus, when the switch 51 is closed, the motors 28can be energized in parallel by closing the switch 4S in either aforward or reverse position, and the speed of the motors can beregulated by adjusting the control rheostat 47. Since the electromagnets31 of each rotor 30 are connected in parallel with the associatedelectric motor 28, the electromagnets 31 are energized simultaneouslywith the electric motor and the current through the electro-magnets 31is regulated by the control rheostat 47. Therefore, the speed of themotors 2S is controlled simultaneously with the degree of current in theelectromagnets 31 associated therewith, whereby the degree of magneticcoupling of the respective electromagnetic rotors 30 with theirassociated driven rotors 25 is regulated simultaneously with theregulation of the speed of the motors.

In operation, with the switches 51 and 45 closed, the motors 28 and theelectromagnetic rotors 30 are simultaneously energized, whereby themotor torque is transmitted to the driven rotors 25 through the magneticeld provided between electromagnets 3l and the permanent magnets 26,whereby the propeller shafts 14 are simultaneously driven and providepropulsion of the boat. The arrangement of the propellers 13 in thechannel 12 vprovides effective longitudinal propulsion of the boat andreduces the turbulence resulting from the rotation of the propellers,since the channel 12 guides the water smoothly past the propellers. Toreverse the direction of movement of the boat or to introduce a brakingforce to retard the speed of the boat, it is merely necessary to reversethe switch 45 and suitably adjust the rheostat 47 to provide the desiredenergization of the motors 28 and the electromagnetic rotors 30associated therewith.

While a specic embodiment of an improved propulsion system for boats hasbeen disclosed in the foregoing description, it will be understood thatvarious modifications within the spirit of the invention may occur tothose skilled in the art. Therefore, it is intended that no limitationsbe placed on the invention except as dened by the scope of the appendedclaims.

What is claimed is:

1. In combination with a boat having an imperforate bottom wallincluding an area of non-magnetizable malterial, a hollow housing havinga closed lower end and an open upper end, means securing said upperhousing end to the underside of said bottom wall, a horizontal propellershaft journaled through said housing, a vertical shaft journaled in saidhousing, said vertical shaft having a lower end operatively connected tosaid propeller shaft and having an upper end, a irst rotor xed on theupper end of said vertical shaft, annular magnet means on said firstrotor, said magnet means positioned adjacent said bottom, a motormounted upon said bottom wall and rising therefrom, said motor having avertical shaft having a lower end, a second rotor fixed on the lower endof said vertical motor shaft, and annular magnet means on said secondrotor in axial alignment with the rst mentioned magnet means andpositioned adjacent to and above said bottom wall, said area ofnon-magnetizable material corresponding to at least the juxtaposed areasof said annular magnet means, said securing means removably securing thehousing to the bottom Wall.

2. In combination with a boat having an imperforate bottom wallincluding an area of non-magnetizable material, a hollow housing havinga closed lower end and an open upper end, means securing said upperhousing end to the underside of said bottom wall, a horizontal propellershaft journaled through said housing, a vertical shaft journaled in saidhousing, said vertical shaft having a lower end operatively connected tosaid propeller shaft and having an upper end, a rst rotor Xed on theupper end of said vertical shaft, annular magnet means on said firstrotor, said magnet means positioned adjacent said bottom, a motormounted upon said bottom wall and rising therefrom, said motor having avertical shaft having a lower end, a second rotor fixed on the lower endof said vertical motor shaft, and annular magnet means on said secondrotor in axial alignment with the iirst mentioned magnet means andpositioned adjacent to and above said bottom wall, said area ofnon-magnetizable material corresponding to at least the juxtaposed areasof said annular magnet means, one of said annular magnet meanscomprising a plurality of permanent magnets and the other annular magnetmeans comprising a plurality of electro-magnets, and energizing meansconnected to said electro-magnets.

References Cited in the file of this patent UNITED STATES PATENTS906,901 Lane et al Dec. 15, 1908 2,127,847 Schulte Aug. 23, 19382,338,341 Lea Jan. 4, 1944 2,506,886 Okulitch et al. May 9, 1950 FOREIGNPATENTS 6,185 Great Britain 1893 176,819 Germany Nov. 8, 1906 448,074Great Britain June 2, 1946

